RESUMO
Objective To study the expression level of cathepsin S in elderly patients with different degree of coronary heart disease(CHD),and to evaluate the correlation between cathepsin S level and the severity of CHD.Methods A total of 126 elderly patients with CHD were enrolled,including 36 cases with acute myocardial infarction(group AMI),48 cases with unstable angina(group UAP),and 42 cases with stable angina(group SAP).During the same period,40 healthy subjects were selected as controls.Venous blood was collected immediately after admission.Arterial blood was taken through radial/femoral artery sheath in AMI patients who underwent primary percutaneous coronary intervention,and coronary arterial blood was taken in AMI patients undergoing intracoronary thrombus aspiration.SYNTAX score was assessed in patients undergoing coronary angiography.Serum levels of high sensitivity C reactive protein(hs-CRP),matrix metalloproteinase-9 (MMP-9) and cathepsin S were determined in all specimens and compared between groups.Results Serum levels of cathepsin S,MMP-9 and hs-CRP were higher in CHD patients than in the control group(P＜0.05).Among CHD patients,group AMI had the highest serum levels of cathepsin S,MMP-9 and hs-CRP,followed by group UAP and group SAP(F =106.830,197.035 and 310.442,all P =0.000).Spearman's rank correlation test suggested that cathepsin S level was positively correlated with serum levels of MMP-9 (r=0.816,P =0.000)and hs-CRP(r =0.827,P =0.000).SYNTAX score was positively correlated with serum levels of cathepsin S(r=0.581,P=0.000),MMP-9(r=0.511,P=0.000),and hs-CRP (r=0.557,P =0.000).Among the 24 patients with AMI who underwent intracoronary thrombus aspiration,the levels of cathepsin S,MMP-9 and hs-CRP were higher in coronary artery blood than in peripheral artery blood (t =217.288,3.177 and 681.479,all P =0.000).Cathepsin S and hs-CRP levels in peripheral arterial blood had positive correlations with those in coronary arterial blood respectively(r =0.962 and 0.494,P =0.000 and 0.014),but such correlation between in peripheral arterial blood versus in coronary artery blood was not found in MMP-9 levels (r =-0.188,P =0.380).Conclusions Serum cathepsin S level is higher in elderly CHD patients than in healthy people,increases along with the increased severity of CHD,and positively correlates with the degree of coronary stenosis.
RESUMO
The effect of the autonomic nerves on the transmural dispersion of ventricular repolarization (TDR) under acute myocardial ischemia in intact canine was investigated. Using the monophasic action potential (MAP) recording technique, MAPs of the epicardium (Epi), mid-myocardium (Mid) and endocardium (Endo) were recorded simultaneously by specially designed plunge-needle electrodes at the left ventricular free wall under acute myocardial ischemia in 12 open-chest dogs. MAPD90 and TDR among three myocardial layers as well as the incidence of the early afterdepolarization (EAD) before autonomic nervous stimulation and during autonomic nervous stimulation were compared. It was found that 10 min after acute myocardial ischemia, TDR was increased from 55 +/- 8 ms to 86 +/- 15 ms during sympathetic stimulation (P 0.05). The EAD was elicited in the Mid of 2 dogs (16%) 10 min after acute myocardial ischemia, but the EAD were elicited in the Mid of 7 dogs (58%) during sympathetic stimulation (P < 0.01). It was concluded that: (1) Sympathetic stimulation can increase the transmural dispersion of repolarization and induce early afterdepolarizations in the Mid under acute myocardial ischemia, which provide the opportunity for the ventricular arrhythmia developing; (2) Parasympathetic stimulation has no significant effect on the transmural dispersion of repolarization under myocardial ischemia.
Assuntos
Potenciais de Ação/fisiologia , Sistema Nervoso Autônomo/fisiopatologia , Estimulação Elétrica , Ventrículos do Coração/inervação , Ventrículos do Coração/fisiologia , Isquemia Miocárdica/fisiopatologia , Junção NeuromuscularRESUMO
The effect of the autonomic nerves on the transmural dispersion of ventricular repolarization (TDR) under acute myocardial ischemia in intact canine was investigated. Using the monophasic action potential (MAP) recording technique, MAPs of the epicardium (Epi), mid-myocardium (Mid) and endocardium (Endo) were recorded simultaneously by specially designed plunge-needle electrodes at the left ventricular free wall under acute myocardial ischemia in 12 open-chest dogs. MAPD90 and TDR among three myocardial layers as well as the incidence of the early afterdepolarization (EAD) before autonomic nervous stimulation and during autonomic nervous stimulation were compared. It was found that 10 min after acute myocardial ischemia, TDR was increased from 55 +/- 8 ms to 86 +/- 15 ms during sympathetic stimulation (P < 0.01). The TDR (53 +/- 9 ms) during parasympathetic stimulation was not significantly different from that of the control (55 +/- 8 ms) (P > 0.05). The EAD was elicited in the Mid of 2 dogs (16%) 10 min after acute myocardial ischemia, but the EAD were elicited in the Mid of 7 dogs (58%) during sympathetic stimulation (P < 0.01). It was concluded that: (1) Sympathetic stimulation can increase the transmural dispersion of repolarization and induce early afterdepolarizations in the Mid under acute myocardial ischemia, which provide the opportunity for the ventricular arrhythmia developing; (2) Parasympathetic stimulation has no significant effect on the transmural dispersion of repolarization under myocardial ischemia.